Fuel Knock ?????

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Jun 11, 2012 | 11:08 AM

#16

JonathanN

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From: Garden City, KS

I'd stil find out if it does it when it goes into decel (injectors turn off when coasting)... That right there will tell you if it's fuel/combustion-related.

Jun 11, 2012 | 12:23 PM

#17

Bonanza35

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From: Norco,CA

Quote:

Originally Posted by JonathanN

I'd stil find out if it does it when it goes into decel (injectors turn off when coasting)... That right there will tell you if it's fuel/combustion-related.

How can they turn off. The truck would stall! I can only here mine at idle. If you park next to walls, or parking structure it can be loud.

Chet

Jun 11, 2012 | 12:55 PM

#18

JonathanN

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From: Garden City, KS

Decel is when the injectors stop firing when you're coasting, using the compression of the motor to help slow the truck down. Try it next time you're going down the interstate and you'll see what I'm talking about.

Jun 11, 2012 | 04:58 PM

#19

Bobbys Big Red Rig

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From: Anderson SC

Quote:

Originally Posted by Bonanza35

Being you think you got all the air out of the system thur the fuel tank, which causes fuel knock maybe a bad o-ring. Had one guy on here that was going to change #8 with #2, and found the o-rings on #2 were bad. He did replaced o-rings and did put #2 with #8 and knock was gone. Never take anything for granite. Good luck,

Chet

The guy does have a bad history with o'rings. Hub bearings went bad on me less than 5k miles after I bought it from him. He had put a set on that same year, he left the o'rings off. Had a few other repairs he did on the truck and some of my family cars, if it had an o'ring it had to be redone. Well most of the time. Thought if it was an o'ring issue I would see smoke or see where it was using oil? I have neither. Wish I had money for stage 2's while in there but that will have to wait.

Jun 11, 2012 | 04:59 PM

#20

Bobbys Big Red Rig

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From: Anderson SC

Quote:

Originally Posted by JonathanN

Learned something new

Jun 11, 2012 | 05:03 PM

#21

Bobbys Big Red Rig

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From: Anderson SC

Quote:

Originally Posted by Tugly

Here is the knock I had before replacing two injectors - it only did this when really warm and in gear.

7.3L Injector Noise - YouTube

Can't say it is the same knock, of course I can't say it's not either

Jun 11, 2012 | 05:17 PM

#22

Bobbys Big Red Rig

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From: Anderson SC

I still have a couple of months before shoulder is heal enough to work on truck, rotator cuff surgery. Swapping FRx for 2nd Gen FRx, Replacing Glow Plugs, Doing .50 cent Mod, Checking O'rings, Torquing Injectors. All but checking O'rings are things I was going to do even if it did not knock. If y'all come up with something else let me know.
Clay if your out there watching, the shoulder is why I have not ordered lately

Jun 12, 2012 | 12:45 AM

#23

Bonanza35

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From: Norco,CA

Quote:

Originally Posted by Bobbys Big Red Rig

If you're going to check the o-rings you'd be better to just replace them. There cheap enough and shouldn't be taken out and then back in, A least thats what i'd been told.

Chet

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Jun 14, 2012 | 12:10 PM

#24

Bobbys Big Red Rig

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From: Anderson SC

Injector Fever

Now I am trying to resist the urge to upgrade injectors while I am in there. At this time I can't do it without the help of VISA

. Must be strong, must be strong.........................
May have to clean out my basement on Craigs List

Jun 16, 2012 | 05:59 PM

#25

Bobbys Big Red Rig

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From: Anderson SC

7.3L Fuel Knock - YouTube
I have not learned how to upload video yet, but that is the youtube link with a video for hearing the knock. Hear it at idle and moving in slow traffic. Normal rattle when drive at Hwy speed. Can't here if I am going down a hill and let off throttle (decel).

Jun 16, 2012 | 06:01 PM

#26

Bobbys Big Red Rig

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From: Anderson SC

Guess I figured out how to post a video afterall

Jun 16, 2012 | 06:31 PM

#27

Christof13T

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From: North Georgia

Quote:

Originally Posted by Tugly

Here is the knock I had before replacing two injectors - it only did this when really warm and in gear.

7.3L Injector Noise - YouTube

this is pretty much the exact same knock im hearing from my passengers side.. sounds like its up around #1 or #2
how can i check them ?
do i really have to pop her vc cherry?
maybe a bottle of lucas injector cleaner before i crack it open?

oh

btw...

xtof

Jun 16, 2012 | 08:02 PM

#28

Bonanza35

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From: Norco,CA

This is exactly what I have from time to time. It was really bad, then I put Clay's FRX on and it cut it in half. Before I did that, I had a freind at ford check it. He shut off each injector and said it was number 8 on mine. It went away for a while but just also came back. I'm going to order one new injector, and o-rings to see if this cures it before I order my stage 2's. I don't want that problem with them. Let me know what you decide to do and if it works. I'll post as well. Mit be a couple of weeks for I install mine, but I'll post.

Chet

Jun 16, 2012 | 08:45 PM

#29

Christof13T

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From: North Georgia

mine will have to wait for a few weeks as well... if all goes well tuesday, i will have a shiny new communications job working out in the texas desert. after a few paychecks ill start my ordering habbit with dieselorings, riffraff, and dp. my thoughts are... the motor is good and broke in at 400k. so why not just go big, and do it right... once. so i dont have to muck with it...

stage 2 injectors, dp f5, intake upgrade, either go thru my turbo or just get one of them spiffy ported doo dads, replace bowl for regulator, frx, and not sure what else... maybe t500

xtof